The present invention relates to an automatic apparatus for transferring cigarette containers from devices arranged to fill such containers to hopper loading mechanisms in packaging machines for forming packets of cigarettes in cigarette manufacturing plants.
As known, the plants used at present for manufacturing cigarettes comprise two main types of machine, i.e.
(I) Cigarette producing machines which start production from cut up and cured tobacco leaves, usually called cigarette manufacturing machines, and
(II) Cigarette packaging machines.
The machines of the latter type, i.e. the so-called packaging machines, usually comprise:
(1) Machines for producing packets of cigarettes usually called packeting machines;
(2) Machines for producing packs of cigarette packets usually called packing or pack-forming machines, and
(3) Wrapping machines for wrapping either single packets of cigarettes, also called cellophaning machines, or single packs of cigarette packets, usually called over-wrapping machines, the cellophaning machines being arranged between the packeting machines and the packing machines, and the over-wrapping machines being placed downstream of or after the packing machines.
It is also known that various kinds of cigarette manufacturing machines referred to at I) above are adopted in practice and operate at a respective output speed of 2000 to 4000 cigarettes per minute.
For the packaging machines mentioned at II) above, there are types of packeting machines (paragraph II-1) which operate at output speeds of 100 or 200 and up to 400 packets of cigarettes per minute, whereas the production rate of various types of packing or pack-forming machine (paragraph II-2) is a function of the number of packets in each single pack. Among the wrapping machines (see paragraph (11-3) II-3) wrapping single packets of cigarettes, the applicant's assignees' cellophaning machine which can wrap 400 packets of cigarettes per minute is widely used, whereas single packs are usually wrapped by means of over-wrapping machines which operate at the same output speed as that of the packing or pack-forming machines co-operating therewith.
From the output speeds of the various types of machine in use at present, it appears that, depending on the types of machine used in forming the system or plant, a packeting machine can absorb the production or output of one to three manufacturing machines, whereas a cellophaning machine can deal with the output of one to three packeting machines.
As known, cigarettes are transferred from the manufacturing machine-(s) to the packeting machine substantially in two different ways, i.e.
(a) either by unloading the cigarettes into containers at the outlet of the cigarette manufacturing machine(s), the containers being then transferred and unloaded into assembling or grouping hopper arranged to feed the packeting line of the packeting machine,
(b) or by directly connecting such outlet of the cigarette manufacturing machine(s) to the grouping hopper arranged to feed the packeting line of the packeting machine, by conveyors feeding streams of individual cigarettes, as in the applicant's applications Ser. Nos. 651,332; 651,334; 651,335; and 651,345.
The present invention concerns that branch of the art which relates to the feeding system for the packeting machine handling cigarettes produced by the manufacturing machine or machines referred to at paragraph a) above, and relates in particular to a feeding system for supplying cigarettes grouped in containers to the hoppers of the packaging machines for forming packets of cigarettes. More particularly it relates to an apparatus for transferring said containers from the means arranged to fill them to mechanisms arranged to load the hopper of the packaging machine, in a fully automatic way.
As known, the conventional cigarette containers, formed of parallelepipedic upwardly open boxes which are also open on one side and are filled by mechanical and/or pneumatic devices co-operating with the cigarette manufacturing machine, are transferred to the loading means of said hopper either manually or by means of automatically or semiautomatically operating apparatuses.
By the progress of the art, packeting machines for forming packets of cigarettes of the type described for example in U.S. Pat. No. 3,628,309 of the same applicant's assignees, were devised to operate at an output speed such as to absorb the output of one to three cigarette manufacturing machines.
Accordingly, the operating continuity and thus the efficiency of a packaging machine of the above-mentioned type depends on the continuity of operation of no less than three manufacturing machines and is thus negatively affected by the inevitable stops due to both accidents and normal maintenance of such machines. In view of the need for a high efficiency and of the possibility that such inconvenience occur, the applicant's assignees have devised, as described in their Pat. No. 3,679,079, an apparatus for feeding containers to a packaging machine of the type operating at a very high speed.
Such apparatus which is manually supplied with containers from the manufacturing machines, comprises a transfer means acting as a store or magazine for containers, to be used only while one or more of the manufacturing machines are stationary.
In this way, the operating continuity of the packaging machine is ensured even in the unfortunate case of the simultaneous stop of all the manufacturing machines, and thus the packaging machine is able to automatically operate at its maximum efficiency until said store is fully exhausted. Once they have been emptied, the containers are sent back to a single transfer means from which they are manually removed and distributed to the various manufacturing machines.
In conclusion, the feeding apparatus disclosed in the above-mentioned patent 3,679,079 receives the full containers from the manufacturing machines, and unloads the empty containers which are supplied back to said manufacturing machines by manual operations.